Exercise as it relates to Disease/Exercise tolerance with Hemochromatosis

What is Hemochromatosis? edit

Hemochromatosis is a disease that causes the body to absorb more Iron than it needs. The body has no way of expelling excess Iron and the levels can become toxic without intervention.[1]

Causes edit

Primary Hemochromatosis is an autosomal recessive genetic disease, meaning a child must inherit a mutated HFE gene from both parents to develop the disease. There is a 25% chance of this occurring if both parents carry one mutant gene. There are a number of other gene mutations that cause symptoms similar to Primary Hemochromatosis known as non-HFE Hemochromatosis. Liver disease and excess alcohol have also been shown to cause Iron overload.[1][2][3]

Prevalence edit

Hemochromatosis is most common in people of northern European decent, affecting around 1 in 250 people. It has been called the Celtic Curse due to it high prevalence in people of Irish Heritage, about 93% are carriers. People with African or Asian heritage are least likely to be affected.[1][2][3][4]

Living with Hemochromatosis edit

Symptoms[2][5] edit

Symptoms are often not observable until a patient is 30 – 50 years of age. The symptoms are also not distinctive which can lead to diagnosis being difficult.

Symptoms of Hemochromatosis include:

  • Tiredness/Fatigue
  • Joint Pain
  • Darkening or Bronzing of Skin
  • Reduced sexual function

Effects of Hemochromatosis[1][2] edit

If left untreated a build up of Iron can cause:

  • Liver diseases.
  • Arrhythmias, Cardiomyopathy and Heart Failure
  • Arthritis
  • Diabetes

Diagnosis edit

Hemochromatosis shares a lot of symptoms with other common diseases.[2] This often slows the process of diagnosis, as other diseases are considered before Hemochromatosis. An initial diagnosis is made via a blood test. If a blood test shows high Transferrin or Serum Iron levels, then a Liver function and Liver biopsy are used to test Liver damage and Iron levels in the liver. Genetic testing may be used to check for the mutant gene - not everyone who has the two required mutant genes will develop symptoms or side effects.[5]

Treatment edit

Treatment is easy, the most common treatment is phlebotomies, or blood letting.[5] This is as simple as donating blood at the Red Cross and the blood can be used as normal, initially phlebotomies may be needed every two weeks until Iron levels are reduced to normal, then every 12 weeks to maintain levels.[1][6] Along with regular blood tests this is usually enough to keep iron levels within a normal range and prevent symptoms and side effects. If phlebotomy is not possible Iron Chelation Therapy uses drugs to remove excess iron from the body.[5]

Exercise Tolerance edit

Diseases that can develop as a result of untreated hemochromatosis such as diabetes and arrhythmias cause their own concerns when exercising. Current evidence suggests that properly controlled hemochromatosis does not have any negative effects on quality of life or life expectancy.[2]
The research to date into the effects of hemochromatosis on exercise is limited. There is evidence that even properly treated hemochromatosis may cause a reduced exercise capacity in sufferers. This is probably due to reduced oxygen uptake as studies have shown no change in left ventricular function.[7][8] Phlebotomy appears to have no effect on exercise capacity.[7] Studies of mice show excess iron can cause increase Reactive Oxygen Species, which can reduce endurance, strength and muscle mass.[9]
The symptoms and effects of hemochromatosis may limit exercise tolerance. Someone who experiences tiredness, fatigue or joint pain may not exercise to avoid exacerbating these symptoms. Excess iron may increase the risk of joint damage and replacement, and that traditional treatment does not reduce iron build up in joint tissue.[10][11]

Recommendations edit

Early detection is the key to treating hemochromatosis and preventing negative side effects:

  • Those of European descent may choose to be tested for the hemochromatosis gene mutation to enable quicker diagnosis if symptoms develop.
  • See a doctor if symptoms develop.
  • Inform family of any diagnosis and suggest they are tested.

Further reading edit

Haemochromatosis AustraliaUS - NIH: Hemochromatosis

References edit

  1. a b c d e Haemochromatosis Australia: Explanation. (2012, 14 Oct 2012). 2013, from http://haemochromatosis.org.au/
  2. a b c d e f Better Health Channel - Hemochromatosis. (2012). State Government of Victoria. From, http://www.betterhealth.vic.gov.au/bhcv2/bhcarticles.nsf/pages/Haemochromatosis
  3. a b Byrnes, V., Ryan, E., Barrett, S., Kenny, P., Mayne, P., & Crowe, J. (2001). Genetic hemochromatosis, a Celtic disease: is it now time for population screening?. Genetic testing, 5(2), 127-130.
  4. Meeker, J. A., Miller, S. M., & PhC, M. T. (2005). Hereditary hemochromatosis. MEDICAL LABORATORY OBSERVER, 37(10), 10.
  5. a b c d National Heart, Lung and Blood Institute: Explore Hemochromatosis. (2011). 2013, from http://www.nhlbi.nih.gov/health/health-topics/topics/hemo/
  6. Goot, K. (2013). Elevated serum ferritin: What should GPs know? 29-08-2013. from http://resources.transfusion.com.au/cdm/ref/collection/p16691coll1/id/564
  7. a b Davidsen, E. S., Liseth, K., Omvik, P., Hervig, T., & Gerdts, E. (2007). Reduced exercise capacity in genetic haemochromatosis. European Journal of Cardiovascular Prevention & Rehabilitation, 14(3), 470-475.
  8. Shizukuda, Y., Bolan, C. D., Tripodi, D. J., Yau, Y.-Y., Smith, K. P., Sachdev, V., et al. (2006). Left ventricular systolic function during stress echocardiography exercise in subjects with asymptomatic hereditary hemochromatosis. The American journal of cardiology, 98(5), 694-698.
  9. Reardon, T. F., & Allen, D. G. (2009). Iron injections in mice increase skeletal muscle iron content, induce oxidative stress and reduce exercise performance. Experimental physiology, 94(6), 720-730.
  10. McCurdie, I., & Perry, J. D. (1999). Lesson of the week: Haemochromatosis and exercise related joint pains. BMJ: British Medical Journal, 318(7181), 449.
  11. Elmberg, M., Hultcrantz, R., Simard, J. F., Carlsson, Å., & Askling, J. (2013). Increased Risk of Arthropathies and Joint Replacement Surgery in Patients With Genetic Hemochromatosis: A Study of 3,531 Patients and Their 11,794 First‐Degree Relatives. Arthritis care & research, 65(5), 678-685.